CQT2010 problematic output

It seems I messed up something when updating nnAudio from 0.1.15 to 0.2.0. The output for CQT2010 is very different from CQT2010v2. I suspect something is wrong during downsampling. But I don’t have time to debug at the moment, will post this as an issue to reminder me later. Or if anyone knows the solution to this problem, a pull request is welcome.

The following code produces the above-mentioned issue. The code below is using nnAudio 0.2.2

import torch
import torch.nn as nn
from torch.nn.functional import conv1d, conv2d

import numpy as np
import torch
from time import time
import math
from scipy.signal import get_window
from scipy import signal
from scipy import fft
import warnings
from torch.nn.functional import fold, unfold
import nnAudio.Spectrogram as Spectrogram_old
from scipy.signal import chirp, sweep_poly
from nnAudio import Spectrogram

# Linear sweep case
fs = 44100
t = 1
f0 = 55
f1 = 22050
s = np.linspace(0, t, fs*t)
x = chirp(s, f0, 1, f1, method='linear')
x = x.astype(dtype=np.float32)
device='cpu'

n_bins = 100
bins_per_octave=12
window = 'hann'
filter_scale = 2
# window='hann'
normalization_type = 'wrap'

# Complex
stft2 = Spectrogram.CQT2010v2(sr=fs, fmin=f0, filter_scale=filter_scale,
                 n_bins=n_bins, bins_per_octave=bins_per_octave, window=window)
X2 = stft2(torch.tensor(x, device=device).unsqueeze(0), normalization_type=normalization_type)
X2 = torch.log(X2 + 1e-2)

#     np.save("tests/ground-truths/linear-sweep-cqt-2010-mag-ground-truth", X.cpu()) 


X3 = librosa.cqt(x, sr=fs, fmin=f0, filter_scale=filter_scale,
                 n_bins=n_bins, bins_per_octave=bins_per_octave, window=window)
X3 = np.log(abs(X3) + 1e-2)

stft1 = Spectrogram.CQT2010(sr=fs, fmin=f0, filter_scale=filter_scale,
                 n_bins=n_bins, bins_per_octave=bins_per_octave, window=window, pad_mode='constant')
X1 = stft1(torch.tensor(x, device=device).unsqueeze(0), normalization_type=normalization_type)
X1 = torch.log(X1 + 1e-2)

fig, axes = plt.subplots(1, 2, figsize=(12, 4), dpi=200)
axes[0].imshow(X1[0,:,:], aspect='auto', origin='lower')
axes[0].set_title('CQT2010')
axes[1].imshow(X2[0,:,:], aspect='auto', origin='lower')
axes[1].set_title('CQT2010v2')
# axes[1,0].imshow(X3[:,:], aspect='auto', origin='lower')

[KinWaiCheuk]

would you mind if I do the pull request and you try it on yours?

Definitely, a pull request is welcome. I will try it on my GPU later.

[migperfer]

Sure! Number 1 is already done, let me experiment with how can we do number 2 without breaking things that are working now.